Y. Larochelle

Energy-light relation for CsI(T1) scintillators in heavy ion experiments at intermediate energies

Abstract In this paper an original energy relation for light scintillation in a CsI(T1) detector is established. It is dependent on the charge and mass of the particle (fragment) and is a direct light-to-energy function suitable for the calibration of CsI(T1) detectors used in heavy-ion studies at intermediate energies. Resulting calibration with this function and energy spectra for light ions, obtained from a heavy ion experiment, are presented.

Quasiclassical model of intermediate velocity particle production in asymmetric heavy ion reactions

The particle emission at intermediate velocities in mass asymmetric reactions is studied within the framework of classical molecular dynamics. Two reactions in the Fermi energy domain were modeled,

Origins of intermediate velocity particle production in heavy ion reactions

{}^{58}\mathrm{N}\mathrm{i}+\mathrm{C}

Calibration of Plastic Phoswich Detectors for Charged Particle Detection

and

Pionic Fusion of Heavy Ions

{}^{58}\mathrm{N}\mathrm{i}+\mathrm{A}\mathrm{u}

Dissipative binary mechanisms in 24Mg + 12C collisions at 25A and 35A MeV☆

at 34.5 MeV/nucleon. The availability of microscopic correlations at all times allowed a detailed study of the fragment formation process. Special attention was paid to the physical origin of fragments and emission timescales, which allowed us to disentangle the different processes involved in the midrapidity particle production. Consequently, a clear distinction between a prompt preequilibrium emission and a delayed aligned asymmetric breakup of the heavier partner of the reaction was achieved.

Statistical and sequential breakup of 24Mg in peripheral reactions at intermediate energies

In this paper, we report for the first time clear distinctions between these prompt processes and an alternative phenomenon of delayed aligned asymmetric breakup that populates the intermediate-velocity zone by a deformation rupture of mainly the heavier of the colliding partners in mass asymmetric collisions. These distinctions were observed experimentally with intermediate-velocity particle correlation analysis of Ni+C and Ni+Au reac

Fine structure in proton emission

The response of an array of plastic phoswich detectors to ions of 1 ≤ Z ≤ 18 has been measured from EA = 12 to 72 MeV. The detector response has been parameterized by a three parameter fit which includes both quenching and high energy delta-ray effects. The fits have a mean variation of ≤4% with respect to the data.

Time scale in 24Mg projectile breakup at 25A and 35A MeV

The previously unobserved phenomenon of heavy-ion pionic fusion is the ideal tool for investigation of coherent mechanisms of pion production, since it since it is the only pionic channel open very near absolute threshold, where the contribution from on-shell nucleon-nucleon mechanisms is the smallest. We begin this paper with a discussion of the existing data on heavy-ion pion production at low energies and review the models intended to provide the requisite coherent pion production mechanisms. We then present our measurement of the 12C(12C, 24Mg)π 0 and 12C(12C, 24Na)π + cross sections at E cm = 137 MeV, which is an order of magnitude closer to threshold than the energy of earlier, inclusive heavy-ion measurements. This constitutes the first experimental observation of the pionic fusion of heavy ions and places severe constraints on the pion production mechanisms. We discuss the impact of this finding on the proposed models, which must now incorporate the kinetic energy of the entire 24-nucleon system as well as the binding energy gained in fusion.

Fusion of radioactive

Abstract A study of the most violent collisions in the 24Mg+12C reactions at 25A and 35A MeV has been carried out. Experimental data, for those events in which the total charge of the system has been detected, are compared to simulations based on statistical fragmentation codes. For violent events, a binary mechanism appears to be competing successfully with compound nucleus formation.